You have 3 18 y/o's, and 3 19 y/o's, and I can see that you really want to start training rook's and sophomores (thought it would be a lot nicer if they are Filipinos). So, yes, getting the gym infrastructure is a great move (I think). It gives a slight boost in a skill that is being currently trained as well as a the other related skills.
Ang maidaragdag ko pa, mas maganda kung magkakaroon ka lamang ng 2-3 trainee bilang nasa Div. III naman tayo. 1 trainee kapag nasa Div. II o PPL dahil na rin sa taas ng lebel ng kompitisyon doon.